When your car's Check Engine light comes on, it's usually accompanied by a sinking feeling in the pit of your stomach. The light could mean a costly problem, like a bad catalytic converter, or it could be something minor, like a loose gas cap.
If you experience any bleeding period after this 20 days, it will probably be the real period. This normally comes at about 4 to 6 weeks after the miscarriage.
After your first trimester, the risk of a miscarriage drops significantly, which is one of the reasons mums-to-be often wait until they reach 12 or 13 weeks to let people know. But there are many other factors to weigh up and only you can decide when you're ready to tell.